As a consequence of intensive pig breeding, in which breeding programs through generations have resulted in sows producing increasingly large litters, the number of stillborn piglets has increased as well as the number of live-born piglets dying after birth. In Denmark in 2013 it was calculated that 22.3% of the born piglets die within the first three weeks of their lives. A total of 9.9% of the piglets were stillborn (cf. Jens Vinther, “Landsgennemsnit for produktivitet i svineproduktionen 2013”, “Videncenter for Svineproduktion”, memorandum no. 1422, 19 Jun. 2014). The high piglet mortality is a problem for ethical as well as animal welfare and economic reasons.
Research has shown that the piglet mortality can be approximately halved by intensive supervision of the farrowing sows and providing of obstetric aid when time intervals between subsequent piglet births exceed a given length (Lene J. Pedersen, Peer Berg et al., “Pattegrisedødelighed i DK—Muligheder for reduktion of pattegrisdødeligheden i Danmark”, Aarhus University, “Det Jordbrugs-videnskabelige Fakultet”, 2010. “DJF Rapport—Husdyrbrug”, Vol. 86. ISBN 87-91949-58-0). Intensive supervision of farrowing sows is very labor demanding when carried out manually. Typically, farrowing sows are only inspected a few times during the day, and it is thus difficult to estimate the time intervals between subsequent births and to provide obstetric aid in time.
An automatic birth monitoring system based on visual cameras (SowCam), which measures the time interval between subsequent births, is known from EP 2786655 A1 and disclosed by Big Dutchman Pig Equipment GmbH: http://www.bigdutchman.com/en/pig-production/news/detail/automatic-birth-monitoring-with-sowcam.html
An automatic birth monitoring system based on visual cameras has been proposed by the innovation consortium StaldTek: http://www.teknologisk.dk/projekter/staldtek-overvaagning-af-farende-soeer/32918
An automatic birth monitoring and alarm system based on visual cameras (ScrofaPARTUM) has been proposed by ScrofaTech: http://scrofatech.com/uploads/catalog/ScrofaPartum.pdf
A birth monitoring system for piglets is known from WO 2008/092258 A1. This system use IR thermal sensing of a piglet to turn on a heating lamp. Only the first piglet is detected using an IR point detection.
Thermographic imaging of livestock is known from US 2014/0015945 A1 and US 20040019269 A1, where it is used, e.g., for detection of inflammations, onset of puberty and estrus.
Measurement of the surface temperature of a sow is known from WO 2009/074153, where it is used to predict the time of birth.